Question: Simplify the expression. $(3a^{4}+6a^{2})(-a^{3}-5a)$
First use the distributive property. $ 3 a^4 (- a^3) + 3 a^4 (-5 a) + 6 a^2 (- a^3) + 6 a^2 (-5 a) $ Simplify. $ - 3a^{7} - 15a^{5} - 6a^{5} - 30a^{3} $ $-3a^{7}-21a^{5}-30a^{3}$ Identify like terms. $ {- 3a^{7}} {- 15a^{5}} {- 6a^{5}} {- 30a^{3}} $ Add the coefficients. $ { -3a^{7}} { -21a^{5}} { -30a^{3}} $